Impregnator



Aprll 16, 1963 M. E.G1NAVEN ETAL 3,085,623

IMPREGNATOR Filed Sept. 15, 1960 2 Sheets-Sheet 1 ,l BY

April 16, 1963 M. E. GINAVEN E-r AL 3,085,623

IMPREGNATOR 2 Sheets-Sheet 2 Filed Sept. 15, 1960 United States Patent Ofi 3,085,623 IMPREGNATOR Marvin E. Ginaven and Albert H. Adams, Springfield, Ohio, assignors to The Bauer Bros. Co., Springfield, Ohio, a corporation of Ohio Filed Sept. 15, 1960, Ser. No. 56,249 9 Claims. (Cl. 162-236) This invention relates to the impregnation of pulp material made from wood chips and like cellular plant stock, and particularly to a generally new apparatus for introducing into the cells and voids of such stock a liquid such as a wash water or a chemical liquor.

The object of the invention is to simplify the construction as well as the means and mode of operation of impregnators whereby such impregnators may not only be economically manufactured, but will be more eiiicient and satisfactory in use, adaptable to a wide variety of application, and be unlikely to get out of order.

An object of the invention is to provide for continuous impregnation of a moving column of plant stock, utilizing feedscrew means, wherein the chip or stock material is exposed to the action of an applied liquid under conditions favorable to a rapid and thorough absorption of the liquid into the stock material.

A further object of the invention is to introduce a new and improved concept in the art of impregnating as described in accordance with which a moving column of the stoclk material is impregnated with greater effectiveness and uniformity and with the application of a substantially constant relatively low liquid pressure.

Still another object of the invention is to carry out impregnation of a kind described in a screw press or the like by means adapted for continuous, trouble-free operation in which minimum or no opportunity is afforded for liquid flow into the press to become obstructed in a manner to elevate the liquid pressure and to yield a lack of uniformity of penetration of the liquid into the mass of stock material.

Still another object of the invention is to provide a liquid ring adapted to be installed in a screw press, as an original or as a replacement part therein, which ring cooperates with the feed screw means of the press to introduce said liquid into the press under conditions favorable to its rapid absorption in and uniform application to the stock material being advanced through the press.

A further object of the invention is to provide an impregnator possessing the advantageous structural features, the inherent meritorious characteristics and the mode of operation herein mentioned.

With the above and other incidental objects in view as will more fully appear in the specification, the invention intended to be protected by Letters Patent consists of the features of construction, the parts and combinations thereof, and the mode of operation as hereinafter described or illustrated in the accompanying drawings, or their equivalents.

Referring to the accompanying drawing wherein is shown one but obviously not necessarily the only form of embodiment of the invention,

FIG. 1 is a fragmentary view in longitudinal section of a screw press as used in pulp production work and equipped with impregnating apparatus in accordance with the illustrated embodiment of the invention;

FIG. 2 is a detailed, enlarged View of the discharge end of the press of FIG. 1;

FIG. 3 is a detailed View in longitudinal section of a liquid inlet ring as embodied in the press of FIGS. l and 2;

FIG. 4 is a front view of the ring of FIG. 3;

3,085,623 Patented Apr. 16, 1963 FIG. 5 is a view like FIG. 3 showing a modified form of liquid inlet ring of a kind adapted for use in a press as shown in FIGS. l and 2; and

FIG. 6 is a front view of the ring of FIG. 5.

Like parts are indicated by similar characters of reference throughout the several views.

Referring to the drawings, there is shown in FIG. l, a screw press of a known kind, adapted to perform work upon wood chips or other partly reduced plant stock as such material passes through the press. The press is only broadly disclosed herein since the impregnating means of the invention, while integrated into the press to become a part thereof, is essentially a means added to or substituted in the press as a unit.

The press is made up of a barrel 10 and rotary feed screw means 11 in the barrel. The wood chips or plant stock is introduced into the press at one end thereof through an opening 12 and is carried by the feed screw means from end to end of the barrel 10 for discharge at `the opposite end thereof, the treated material being carried away from the press to another process stage by means including a duct 13.

The barrel 10 is comprised of sectional pieces arranged in end to end abutting relation with certain sections being made up of a circumferential series of spaced apart screen bars or the like which serve to confine the stock Within the press but permit an escape of fluids, air and liquid, therefrom. Thus, a plurality of longitudinally spa-ced apart cylindrical fittings 14, 15 and 16 may support between them two longitudinal series of screen bars 17 and 18, the several ttings 14-16 and the screen bars 17 and 18 cooperating to define the barrel and its generally cylindrical interior 19. The feed screw means 11 comprises an elongated shaft 2t) longitudinally disposed in the passage 19 and having secured to the surface thereof a combination of helical worms and teeth designed to produce movement of the stock material through the press at varying speeds and under various conditions of compression and iiberization. At what may be considered to be the inlet end of the passage 19, beneath inlet opening 12, the shaft is formed with a relatively wide diameter, short pitch worm 21 designed to pick up relatively large quantities of introduced stock and move it at relatively slow speed into the further reaches of the passage 19. Beyond the worm 21 there is attached to the shaft 20 a series of collars adapted primarily for feeding or for tiberizing or for both. Thus, a `series of collars 22--26 are ysecured to the shaft in longitudinally spaced relation to one another and carry worms or partial worms for advancing the stock material forwardly in the passage 19. Between the collars 22 and 23 is a cylindrical collar 27 secured to the shaft which rotates in alignment with internal abutments 28 on the barrel. The abutments 28 inhibit rotation of the stock material with the feed screw means and contribute a refining action upon the stock in connection with its forcible movement by the worm 22 and with rotation of the collar 27. The latter may have `surface grooves acting as teeth to increase the amount of work performed upon the stock. Intermediate the collars 23 and 24, intermediate the collars 24 and 25 and intermediate the collars 25 and 26 are other collars 29, 31 and 32. These are formed with raised lugs or teeth 33, 34 and 35 respectively and are located in alignment with respective internal barrel abutments 36, 37 and 38. Beyond the several collars as described, and in transverse alignment with the cylindrical fitting 16, is a conical collar 39 on the shaft 20. This collar, in conjunction with the fitting 16, provides a relatively restricted passage 41 serving as the outlet or discharge end of the press passage 19 and communicating beyond the collar 39 with an expansion chamber 42 defined by a cylindrical extension 43. The cylindrical extension 43 projects from the fitting 16 to stationary end plate 44 forming a part of the frame of the press. The shaft 20 extends through and beyond the expansion chamber 42 and Within `the chamber has a worm 40 thereon adapted to mo-ve the stock material through the expansion chamber and into the duct 13.

Wood chips, agricultural residues or like compressible materials are brought to `the screw press in any convenient manner and admitted thereto by way of the inlet opening 12. The admitted material is picked up by the Worm 2l and advanced toward the fitting 15. The screen bars 17 in this area define a gradually reducing diameter of the passage 19 with the result that a progressive compressive force is applied to the material so that the contained air and liquids therein are gradually exhausted or expelled and pass out of the press between the bars 17. Reaching the worm 22, the material continues to be advanced through the passage 19 and it moves through successive feeding and fiberizing stages, as defined by the several described collars, toward the restricting collar 39 at the location of cylindrical fitting 16. As the material is advanced by the worm formations on the rotating shaft, air and liquids continue to be expelled and `the compression exerted upon the material gradually is increased as the material approaches the area of maximum flow resistance as defined by the inwardly facing conical surface on the collar 39. Thus, under conditions of maximum compression, with maximum exclusion of air and liquid, the stock material passes through .the restricted passage 41 and is forced into the expansion chamber 42. There the material is substantially released from compression and passes in a dry, expanded, saturable condition to the control of worm 40.

In accordance with the instant inventive concept the impregnation of the moving column of stock material is carried out Within the expansion chamber 42 where, as noted conditions are ideally present for a thorough wetting of the material. To this end, the cylindrical fitting 16 is constructed as a liquid inlet ring. Referring also to FIGS. 3 and 4, this ring has the form of an annular body 45.

A counterbore in one end of the body 45 defines an interior recessed shoulder 46 with the portion of the body in projecting surrounding relation to the shoulder 46 having the characteristics of a cylindrical sleeve 47. A tapered surface 48 is formed at the inner edge of the sleeve 47. A circumferential series of spaced apart recesses 49 open at their outer ends through the planar surface of the shoulder 46 while their opposite or inner ends have a common communication with an annular groove in the body. One or a plurality of pipes 52 are attached peripherially to the body 45 to communicate with groove 51. Liquids supplied through the pipes 52 reach groove 51 and through it the openings or recesses 49. The latter accordingly serve as liquid fiow passages and discharge the admitted liquid in streams forwardly of the ring and in a direction generally parallel to the longitudinal axis of the ring. In its installation, the ring 16 is mounted in the press with the stepped-down shoulder 46 and the liow passages 49 therein facing the expansion chamber 42. Accordingly the liquid discharge occurring through the ring is delivered to the chamber 42 where it enters the chamber in a direction forwardly thereof or in the same direction as the movement of the stock material therethrough. The worm 40 assists in forming a relatively soft plug of the stock material in the chamber 42 whereby the liquid is not sprayed uselessly through and beyond the chamber. The passages 49 open through tht shoulder 46 at a point between the inner periphery of the ring and the projecting sleeve 47, in the illustrated instance at a point immediately adjacent to the sleeve 47. So located, the liquid ow is parallel to the flow of the solids and cannot be interrupted by a massing of solids at the outlet openings of the passages. The liquid is introduced through a corner of the counterbored ring face, the outlets of the passages 49 being by virtue of the location thereof, virtually by-passed by the stock as it moves through the passage 41 into the chamber 42. The resistance to the entrance of the liquids is at a minimum, as on the order of zero to ten pounds pressure, With the result that the volume of added liquid can be varied widely without basic changes in the impregnation equipment. The flow of liquid into the expansion chamber occurs at spaced points completely around the circumference, although the liquid supply line can be a single pipe into the periphery of the ring. The annular groove 51 provides a uniform pressure to each orifice discharge passage 49. Further, the liquid inlet ring offers a simple means of adapting a standard screw press for liquid impregnation operation, the elements of the impregnation system being merely added to or substituted in the press at the discharge zone thereof.

The liquid inlet ring may assume other forms. For example, as shown in FIGS. 5 and 6, the ring may be adapted for an angular discharge of the liquid into the expansion chamber, as Well as to provide internal abutments for use as breaker bars in the manner of the internal abutments 28, 36, 37 and 38 in the barrel proper. A liquid inlet ring as shown in .FIGS. 5 and 6 is dimensioned substantially like the cylindrical fitting or ring 16 to be substituted therefor in the same environment. It comprises a body 53, an external annular groove 54 supplied by a pipe 55, orifice discharge openings 56, a projecting sleeve 57, and a recessed shoulder 58. In this instance, however, the shoulder 58 is formed with inwardly or radially projecting portions 59, these projections extending inwardly of the normal circumferential plane of the shoulder 58 and acting as breaker bars as noted to obtain a greater compression of the material immediately before expansion and to inhibit rotary movement of the material before expansion. Moreover, the orifice openings 56 are inclined with respect to the longitudinal axis of the ring to discharge in a direction both forwardly of and angularly into the expansion chamber. A more direct injection into the core of the moving mass of material is so achieved. The formation of the breaker bars 59 is such as to permit expansion of the pulp in an approximately 270 position around each orifice opening 56. Accordingly the jet of liquid discharged from each inlet orifice enters a small cavity formed by the extruded fibrous mass and this provides for a more rapid and controlled absorption of the liquid by the fiber bundles.

In accordance with the general concept of impregnating in a screw press environment, the press acts to effect a partial fiberizing of the material under treatment by separating the fibre bundles without appreciable breakage or shortening of the fibre length. Air and moisture are exhausted by compression and the resulting dry, saturable material wih its added exposed surface is allowed to expand into the chamber 42. As the material expands, the voids in the mass are uniformly filled with admitted liquid which uniformly and effectively penetrates the mass of material, the impregnating operation being carried out Without pressure variation and under closely controlled volume flow conditions.

From the above description it will be apparent that there is thus provided a device of the character described possessing the particular features of advantage before enumerated as desirable, but which obviously is susceptible of modification in its form, proportions, detail construction and arrangement of parts without departing from the principle involved or sacrificing any of its advantages.

While in order to comply With the statute the invention has been described in language more or less specific as to structural features, it is to be understood that the in vention is not limited to the specific features shown, but

that the means and construction herein disclosed comprise but one of several modes of putting the invention into into effect, and the invention is therefore claimed in any of its forms or modifications within the legitimate and Valid scope of the appended claims.

Having thus described our invention, we claim:

1. In a screw press having a barrel and a feed screw longitudinally disposed in said barrel for advancing wood chips and like material from end to end thereof; the improvement which resides in a ring integrated into said press as an extension of said barrel and in surrounding relation to said feed screw, said ring including an annular body, a counterbore at one end of said body defining a recessed shoulder provding a planar surface within the circumferential area defined by the outer periphery of said body and approximately at right angles to the longitudinal axis of said body, a circumferential series of liquid flow passages in said body opening through said planar surface, and a liquid inlet in said body in common communication with said flow passages.

2. In a screw press having a barrel and a feed screw longitudinally disposed in said barrel for advancing Wood chips and like material from end to end thereof; the improvement which resides in a ring integrated into said press as an extension of said barrel and in surrounding relation to said feed screw, said ring including an annular body, a counterbore at one end of said body defining a recessed shoulder and a relatively projecting sleeve, a circumferential series of liquid flow passages in said body opening through said shoulder intermediate the inner periphery of said body and said sleeve, and a liquid inlet in said body in common communication with said flow passages.

3. A liquid inlet ring according to claim 2, characterized in that said ow passages are arranged to discharge liquid in streams from said shoulder in a direction forwardly of said sleeve and approximately parallel thereto and to the longitudinal axis of said body.

4. A liquid inlet ring according to claim 2, characterized in that said flow passages are arranged to discharge liquid in streams forwardly of said sleeve and angularly toward the longitudinal axis of said body.

5. In apparatus for the impregnation of cellular plant stock which includes a screw press operable continuously to advance the stock in a partly reduced form and having a discharge end, and an open ended extension on the discharge end of the press defining an impregnation chamber, said press applying compressive forces to the stock which effectively expands into said chamber; the improvement which resides in a ring interposed between said screw press and said extension, said ring having an external liquid inlet and a plurality of circumferential outlets directed for discharge into said chamber.

6. Apparatus according to claim 5, characterized in that said ring is constructed with said outlets directing a liquid discharge parallel to the longitudinal axis of said extension.

7. Apparatus according to claim 5, characterized in that said ring is constructed with said outlet directing a liquid discharge angularly toward the longitudinal axis of said extension.

8. In apparatus for the impregnation of cellular plant stock which includes a screw press operable continuously to advance the stock in a partly reduced form, said press having rotating feed screw means; the improvement which resides in a ring integrated into said press in surrounding relation to said feed screw means, said ring having circumferentially spaced apart inward projections defining with said feed screw means breaker bars, and liquid discharge openings in said ring facing forwardly or in the direction of movement of the stock through the press, said ring having an external liquid inlet in common communication with said outlets.

9. In apparatus for the impregnation of cellular plant stock which includes a screw press operable continuously to advance the stock in a partly reduced form, said press having rotating feed screw means formed at a selected location with an annular collar; the improvement which resides in a ring integrated into said press in surrounding relation to said feed screw means at the location of said collar, said ring having an inner periphery cooperating with said collar to define an annular through opening of reduced area at the location of said collar and surrounding ring, said ring having a passageway communicating with the exterior of the press to receive a liquid under pressure, and said ring further being formed intermediate its inner and outer peripheries to spray the liquid from said passageway in a plurality of circumferentially spaced streams discharging into the press zone beyond the location of said ring and collar in relation to the direction of movement of stock through the press.

References Cited in the file of this patent UNITED STATES PATENTS 1,922,313 Mason Aug. 15, 1933 2,176,902 Horrocks Oct. 24, 1939 2,276,237 Lowry Mar. 10, 1942 2,662,576 Pukacz Dec. 1S, 1953 2,975,096 Ginaven Mar. 14, 1961 

1. IN A SCREW PRESS HAVING A BARREL AND A FEED SCREW LONGITUDINALLY DISPOSED IN SAID BARREL FOR ADVANCING WOOD CHIPS AND LIKE MATERIAL FROM END TO END THEREOF; THE IMPROVEMENT WHICH RESIDES IN A RING INTEGRATED INTO SAID PRESS AS AN EXTENSION OF SAID BARREL AND IN SURROUNDING RELATION TO SAID FEED SCREW, SAID RING INCLUDING AN ANNULAR BODY, A COUNTERBORE AT ONE END OF SAID BODY DEFINING A RECESSED SHOULDER PROVIDING A PLANAR SURFACE WITHIN THE CIRCUMFERENTIAL AREA DEFINED BY THE OUTER PERIPHERY OF SAID BODY AND APPROXIMATELY AT RIGHT ANGLES TO THE LONGITUDINAL AXIS OF SAID BODY, A CIRCUMFERENTIAL SERIES OF LIQUID FLOW PASSAGES IN SAID BODY OPENING THROUGH SAID PLANAR SURFACE, AND A LIQUID INLET IN SAID BODY IN COMMON COMMUNICATION WITH SAID FLOW PASSAGES. 